PROJECT SUMMARY Cerebral ischemia, most notably in the form of stroke, is one of the leading causes of death and disability. Unfortunately, the utilization of tissue plasminogen activator is the only approved therapy for stroke, with limited application potential. Clinical trials testing post-stroke neuroprotective agents have not been successful. Thus, the identification of prophylactic strategies able to induce endogenous neuroprotective mechanisms has high potential for stroke therapy. The therapeutic potential of preconditioning paradigms, in which brief episodes of a sublethal ischemic insult induce robust protection against subsequent ischemic injuries, has been repeatedly demonstrated. Our studies suggests that resveratrol preconditioning can induce a chronic ischemic tolerance that lasts for at least 2 weeks in vivo. The main objective of this proposal is to determine the mechanistic basis of neuroprotection afforded by resveratrol induced preconditioning to help us identify innovative therapeutic strategies that prevent or at least reduce neuronal damage in susceptible patients. We have shown that resveratrol emulated ischemic preconditioning (IPC) in brain in a Sirt1 dependent manner. A major observation emerging from our studies is that resveratrol upregulate BDNF levels. We hypothesize that the transcriptional regulator MeCP2 mediates, at least in part, the neuronal transcriptional responses to Resveratrol. In aim 1, we will test the MeCP2 dependence of RPC-induced chronic ischemic tolerance. The neuroprotective effect of resveratrol will we assessed in control mice and a tamoxifen-inducible neuron-specific Mecp2 knockout mice which will be subjected to focal cerebral ischemia by middle cerebral artery occlusion (MCAo). Aim 2 will assess the ability of RPC to modify MeCP2 dependent gene regulation. For these experiments we will employ in vivo (mouse brain) and ex vivo (organotypic cortical slice cultures) experiments to assay the effect of resveratrol administration on posttranslational modifications of MeCP2, the binding of MeCP2 to chromatin and to its cognate partners. Identification of the mechanisms by which long-lasting neuroprotection elicited by resveratrol will have implications not only in stroke and several other forms of ischemia, such as cardiac arrest, but also other neurological disorders with similar pathology.